Thioether isocyanate adducts

ABSTRACT

Novel thioether isocyanates and isothiocyanates can be produced by the addition of thiols to the olefinic bonds of allyl isocyanates and isothiocyanates. They are useful as pesticides, especially as post-emergence herbicides, and as polymer intermediates.

Unlted States Patent 1191 1111 3,884,951 Oswald May 20, 1975 THIOETHER ISOCYANATE ADDUCTS [56] References Cited [75] Inventor: Alexis A. Oswald, Mountainside, UNITED STATES PATENTS NJ. 2,340,757 3/1938 Kaase et a1. 260/453 3,215,701 11/1965 Pomot 260/453 X [73] Assgneei Exxm Reseafch & Eng'neemg 3,409,631 11/1968 Hollschmidt et a1 260/453 x Company, L1nden, NJ. 3,519,686 7/1970 Nair 260/453 X Filedi J 1 1971 FOREIGN PATENTS OR APPLICATIONS [21] Appl. No.: 107,474 981,346 1/1965 United Kingdom Related Application Data Primary Examiner-Lewis Gotts Division Of S61. NO. 759,200, Sept. ll, 1968, Pat. Assistant Examiner Do]ph Terrence 3597,341- Attorney, Agent, or Firm-J, P. Corcoran; R. .1. Baran [52] US. Cl 260/453 A; 71/98; 7l/l00; [57 ABSTRACT 71/104; 260/75 NT; 260/77.5 AT; 260/448.2 N 1 h d 26O/453 AL 260/453 AR 260,453 ove t 1oet er lsocyanates an 1s ot locyanates can 26(5/454 260/455 A. 260/470 260/481 f be produced by the add1t1on of th1o1s to the olefimc 424/298, 424/302 bonds of allyl isocyanates and isothiocyanates. They [51] [m C] C07c 119/04 are useful as pesticides, especially as post-emergence 1581 11.1.1 416616;:iii'aaayz tx g'aa A, 453 AR herbicides, and as Polymer intermedmes- 3 Claims, No Drawings 1 TIIIOETHER ISOCYANATE ADDUCTS CROSS-REFERENCE TO OTHER APPLICATIONS This application is a divisional of an application bearing U.S. Ser. No. 759,200. filed Sept. 11, I968. U.S. 5 Pat. No. 3,597,341 in the name of Alexis A. Oswald.

PRIOR ART It is known that isocyanates and isothiocyanates react with thiols under ionic conditions, especially at elevated temperatures, to yield thiourethanes. For references see H. L. Snape, Ber. Vol. 18, pages 24-32 (1885); E. Dyer and J. F. Glenn, J. Am. Chem. Soc., Vol. 79, p. 366 (1957); U.S. Pat. No. 2,764,592.

R,R' organic radical; X 0,8

Such formation of thiourethanes is accelerated by ionic catalysts and heating.

However, the prior art has not been cognizant of the selective low temperature reaction of the olefinic group of unsaturated isocyanates and/or isothiocyanates with thiols under free radical conditions to form novel, useful anti-Markovnikov type adducts.

FIELD OF THE INVENTION SUMMARY OF THE INVENTION The novel anti-Markovnikov adducts of this invention are generally prepared in the course of a free radical addition process wherein a variety of thiols can be added to the olefinic double bond of a variety of allylic isocyanates and isothiocyan ites.

In general, the reaction can be depicted by the following reaction scheme wherein X 15 oxygen and sulfur, preferably oxygen, and p and q are each a positive integer from 1 to 30, preferably I to 5, most preferably 1 to 3, with q being equal to or smaller than p and the meaning of the various R groups is defined in the following R"" is a mono-, dior polyvalent organic radical selected from the group consisting of unsubstituted and substituted C to C preferably C to C hydrocarbon radicals whose substituents are sulfur, oxygen and silicon. The hydrocarbon radicals can be open chain and cyclic aliphatic, and aromatic radicals. It is, however, preferred that they should be selected from saturated open chain aliphatic radicals and nonfused benzenoid radicals, such as phenylene with possible phenyl and alkyl substituents, respectively. The nonhydrocarbon substituents of these radicals are preferably selected from the group consisting of chlorine, bromine, C -C alkylthio, hydroxy, C,C alkyloxy, C,-C alkylsulfonyl, phenylsulfonyl, cyano, C C carboalkoxyalkyl, acetyl, nitro.

Examples of the various R"" polyvalent radicals are provided in the specification when discussing monovalent radicals R, divalent radicals R, trivalent radicals R" derived from mono-, diand trithiol reactants. Examples of higher valent radicals are C I-I (CH derived from durene tetrathiol, C(CH OCOCI-I CI-I derived from methane (tetracarbomethoxyethanethiol), polyvalent hydrocarbon radicals derived from polypropylene, polybutadiene, polypropyleneoxide, polypropylenesulfide.

R to R are monovalent radicals selected from the group of hydrogen, methyl, chlorine, cyano, C to C preferably C to C alkylthio substituted methyl, phenylthio substituted methyl and combination thereof. It is, however, preferred that at least 3 of the above R radicals be hydrogen. Furthermore, it is preferred that the two remaining radicals be selected from the group of hydrogen and methyl radicals.

Preferably, the reaction is carried outwith allyl isocyanate or allyl isothiocyanate as indicated by the following scheme (HS),, R"(S CH CH CH N =C X), wherein the meaning of the symbols is the same as given at the earlier equation.

It is more preferredto react all the thiol groups of the wherein p equals q. In general, this reaction may be illustrated with allyl isocyanate and is thiocyanate in accordance with Equation 1 below.

EQUATION 1 wherein X is O or S, product I is formed in major amounts, and product ll is formed in minor amounts, R being C -C hydrocarbyl moiety such as C to C alkyl, C to C monosubstituted alkyl, C, to C disubstituted alkyl, C to C aryl, C to C monosubstituted aryl, C to C disubstituted aryl. The aliphatic moiety has preferably C, to C carbon atoms. The aromatic moiety is preferably phenyl. Preferable substituents are chlorine, bromine, C -C alkylthio, hydroxy, C -C alkyloxy, C -C alkylsulfonyl, phenylsulfonyl, cyano, C -C carboalkoxy alkyl, acetyl, nitro, etc. Substituents, which catalyze the reaction of the thiol groups with the isocyanate or isothiocyanate groups must be absent. Such substituents are all strongly basic and acidic groups such as alkylamino, sulfonic acid, phosphonic acid, etc.

In like manner, substituted allylic isocyanates and isothiocyanates can be reacted with thiols in accordance with the following equation, Equation 2.

EQUATION 2 RS-C C C N C'X RS-C C N C X I I R H R CH R I II v 2-butenethiol, 2,3-epoxypropanethiol, etc.

Typical, non-limiting isocyanate and isothiocyanate reactants of this invention include crotyl isocyanate, 2-methallyl isocyanate, 4-methylthiocrotyl isothiocyanate, 4-phenylthiocrotyl isocyanate, 4-chlorophenylthiocrotyl isocyanate, 4-nitrophenylthiocrotyl isocyanate, 2-chloroallyl isothiocyanate, xylylthiocrotyl isocyanate.

When a dithiol is reacted with an allyl isocyanate or isothiocyanate one or both thiol groups may participate in the addition reaction to the allylic double bond, as is shown in Equation'3 below.

EQUATION 3 wherein R is a divalent organic radical such as Cf-C alkylene, C C phenylene, C -C phenalkylene, e.g. xylylene. The alkylene group can also contain hetero atoms such as S, S0 0, Si(CH groups in which the maximum carbon number of the continuous alkylene unit is twenty, the number of alkyleneheteroatomic group units (11) being 0 to 100, e.g.:

Typical, non-limiting dithiol reactants include 1.3- propanedithiol, l,6-hexanedithiol, cyclooctanedithiol. cyclododecanetrithiol, l,2-ethanedithiol, benzenedithiol, xylylene dithiol, 2-thio-bis-ethanethiol, 2-sulfonyl-bis-ethanethiol, 3-oxy-bis-propanethiol. 3-hydroxy-1,2-propanedithiol, 3-chloro-l ,2- propanedithiol, polyethylenethioetherdithiol, polyethyleneoxidedithiol, polyethylenesulfonedithiol, polypropylenethioetherdithiol, etc.

The monoadduct intermediate of the dithiol-allyl isocyanate intermediate can' undergo a polyselfaddition initiated by heat and/or ionic catalysts to form a polythiourethane, as shown in Equation 4 below.

EQUATION 4 n+1 as R' s cn -ca -cii -N-c-x9 s S(CH2)3NH('1S njswn hn c x wherein n is l to 500, preferably 20 to 200.

Alternatively, the diadduct may be reacted with a diol or dithiol to yield a polyurethane, as shown in Equation 5.

In the case of trithiol reactants, the selective additions to ally] isocyanate and isothiocyanate can be carried out to various degrees, as shown in Equation 6.

EQUATION 6 R n 3 CH2=CHCH NCX wherein l R is a trivalent unsubstituted organic radical containing from 6 to 500 carbon atoms, which radical can be substituted by such atoms as sulfur, oxygen 'and silicon, illustrative examples of these substituted radicals including polythioether, polyether, and polysilane trithiols, etc.; and (2) X is O and S, preferably 0.

Typical, non-limiting trithiol reactants include trimercaptoethyl cyclohexane, tri-mercaptoethylthio cyclododecane, the tri-mercaptoacetic acid ester of trihydroxymethyl methane, the tetra-mercaptopropionic acid ester of pentaerythritol, polypropylenethioethcr trithiol, the di-mercaptoacetic ester of pentaerythritol, the polythiol resulting from polybutadiene excess hydrogen sulfide addition, the hexathiol resulting from trivinyl cyclohexane-hydrogen sulfide addition, the trithiol resulting from polypropylene thioether-dithioltrivinyl cyclohexane addition, etc.

In the case of polythiols the number of allyl isocyanate molecules reacted per molecule of polythiol can equal up to the number of thiol groups in the polythiol. The general reaction is shown by Equation 7.

EQUATION 7 Preferred dithiols are polymethylene and polymethylenethioether dithiols each of which can bereacted with allyl isocyante in accordance with Equation 8.

EQUATION 8 wherein l is l to 12.

A preferred trithiol is the triaddition product of the reaction of polymethylene and polymethylenethioether dithiols with trivinyl cyclohexane, which reaction is shown in Equation 9.

EQUATION 9 Without wishing or intending to be bound by any theory, it is nevertheless believed, from the structure of the adducts obtained, that the selective additions of this invention take place by means of a free radical type chain mechanism and in accordance with the following postulated reaction mechanism.

Initiation RSHa- RS.

initiator Propagation Step (I RS.+ CH =CHCl-l --NCO-' I RSCH CHCH --NCO Step (2) RS CH --CHCH NCO RSI-I RSCl-l -CH CH NCO RS.

REACTION CONDITIONS The reaction temperatures employed in this invention are preferably kept below 100C., most preferably below about 50C, in order to avoid concurrent ionic reactions of the isocyanate group which result in the formation of by-products. The lower limit of the reaction temperature range is defined by the freezing point of the reaction mixture employed, reaction initiation, and the cost of refrigeration. Reaction temperatures are between about -l50 and about +100C., preferably between about and about +50C. For the initiation of the low temperature, selective free radical reactions, nonchemical initiators are preferred, such as ultraviolet light, gamma radiation, etc. However, chemical initiators can also be used below the temperature limits of the reactions. For example, chemical initiators such as peroxides, derived from boron alkyls are suitable low temperature initiators. Other chemical initiators include azo compounds, such as bis-azo-i-.

butyronitrile, etc.

Usually the reactions of this invention are carried out with equivalent amounts of reactants in the liquid phase at atmospheric pressures. If the thiol reactant is gaseous at the reaction temperature, superatmospheric pressure can be used to keep it in the liquid state. Alternatively, such a thiol as, e.g., ethanethiol, can be slowly introduced into the radiated, liquid allylic isocyanate compound. In general, the isocyanate reactants are good solvents for the thiols. Solid thiols can essentially be dissolved in the isocyanate reactants to obtain liquid reaction mixtures. However, the use of nonreactive solvents at times can be desirable. Exemplary of suitable solvents are the open-chain and cyclic hydrocarbons such as heptane, cyclohexane, benzene, xylene, etc.; aliphatic sulfides such as dimethyl sulfide; dialkyl When allylic isocyanates or isothiocyanates of this .invention are reacted with polythiols, it is to be understood that the resulting reaction can be either a partial one or can be run until completion.

ethers such as diethyl ether; esters such as ethyl acetate; dialkyl sulfones such ad diethyl sulfone; etc.

Although the reactants are usually employed in equivalent amounts, an excess of either reactant be- EQUATION IO CII 35H 8x08 8 S v CH3S CH2) 3NCO cu SH (2) CH3S(CH2)3NCO 3 9 The dithiol reactants of this invention such as e.g., ethane dithiol, can be reacted with half of the stoichiometric requirements of allyl isocyanate to yield a thiol isocyanate product which is itself subject to polyautoaddition to thereby result in a polyurethane product in accordance with the following equation, Equation 1 l.

EQUATION l l n HS(CH2)2SH n CH2=CHCH2NCO n HS(CH2)2S(CH2)3NCO Alternatively, trithiols such as polythioether trithiols can be reacted with an excess of allyl isocyanate to convert them to the corresponding polythioether triisocyanates. The excess allyl isocyante is then removed by distillation.

In general, the monothiol adducts of this invention are characterized by the formulae:

&3 a RS-C-C-C-N=C=X I I I R H R and CHR

wherein R, R R and X are as previously defined in Equation 2.

The preferred monothiol adducts .of this invention have the formula Illustrative nonlimiting examples of R include methyl,

octadecyl, t-butyl, phenyl, naphthyl, anthryl, cyclohexyl, 3-chloropropyl, trichlorophenyl, hydroxyethyl, nitroaphthyl, methanesulfonylpheny], carboethoxymethyl, epoxypropyl, cyanoethyl, acetylphenyl, etc.

The preferred monothiol adducts include ethylthiopropyl isocyanate, ethylthiopropyl isothiocyanate, cyanoethylthiopropyl isothiocyanate, dichloropropylthiopropyl isothiocyanate, hexadecylthiopropyl isothiocyanate, naphthylthiopropyl isothiocyanate, etc.

In general, the dithiol adducts of this invention are characterized by the following formulae:

wherein R, X, and n are as previously defined in Equations 3 and 4.

Illustrative, nonlimiting examples of R include propylene, trimethylene, ethylene, xylylene, phenylene, polyethylene thioether, polypropylenethioether, polyethyleneoxide, polyethylenedimethylsilane, polyethylenesulfone, polydodecamethylenethioether, etc.

In general, the trithiol adducts of this invention are characterized by the following formula:

wherein R" is as previously defined in Equation 6.

The polythiol adducts of this invention are generally described by the following formula:

tants as alcohols, thiols, acids, amines, oximes, water,

etc. Moreover, the products derived from the reaction of dithiols, and polythiols with allylic isocyanates are especially useful in polymer chemistry as monomers and cross-linking agents.

The diisocyanate, triisocyanate and polyisocyanate containing adducts of di-, tri-, and polythiols are mainly utilized in polymer chemistry as monomer components with diols, triols, polyols and diamines, triamines, polyamines, and water. Their reaction as monomer components leads to polyurethanes and polyureas. Difunctional diisocyanates when reacted with diols and diamines yield linear polymers. Polyfunctional isocyanates are useful as crosslinking agents.

As previously noted, the anti-Markovnikov adducts of this invention are also useful as pesticides, particularly as post-emergence herbicides. For pesticidal uses it is preferable that the adduct be derived from a mono or dithiol. As the other component an allylic isothiocyanate is preferred. It is furthermore preferred that less than 500. The dithiol used in the preparation of pesticides is preferably a C to C polymethylene dithiol.

When used as post-emergence herbicides, the biologically active ingredients are preferably formulated with a suitable carrier or diluent or combinations thereof.

The term carrier or diluent as used herein means a material, which can be inorganic or organic and synthetic or of natural origin, with which the active ingredient of this invention can be mixed or formulated to facilitate its storage, transportation and handling, and application to the plants, e.g., weeds, to be treated. The carrier is preferably biologically and chemically inert and, as used, can be a solid or a fluid. When solid carriers are used, they are preferably particulate, granular, or pelleted; however, other shapes and sizes of solid carriers can be employed as well. Such preferably solid carriers can be naturally occurring minerals although subsequently subjected to sieving, sieving purificaation, and/or other treatments, including for example, gypsum; tripolyte; diatomaceous earth; mineral silicates such as mica, vermiculite, talc, and pyrophyllite; clays of the montmorillonite; kaolinite, or attapulgite groups; calcium or magnesium limes; or calcite and dolomite etc. Carriers produced synthetically, as for example, synthetic hydrous silica oxides and synthetic silicates can also be used, and many proprietary products of this type are available commercially. The carrier can also be an elemental substance such as sulfur or carbon, preferably an activated carbon. If the carrier possesses intrinsic catalytic activity such that it would decompose the active ingredient, it is advantageous to incorporate a stabilizing agent, as for example, polyglycols such as diethylene glycol to neutralize this activity and thereby prevent possible decomposition of the active and anti-Markovnikov ingredient.

For some purposes, a resinous or waxy carrier can be used, preferably one which is solvent soluble or thermoplastic, including fusible. Examples of such carriers are natural or synthetic resins such as coumarin, resin, rosin, copal, shellac, dammar, polyvinyl chloride, styrene polymers and copolymers, a solid grade of polychlorophenol such as is available under the registered trademark Arochlor, a bitumen, an asphalite; a wax, for example, beeswax, or a mineral wax such as a paraffin wax or Montan wax, or a chlorinated mineral wax, or a micro-crystalline wax such as those available under the registered trademark Mikrovan wax. Compositions comprising said resinous or waxy carriers are preferably in granular or pelleted form.

Fluid carriers can be liquids, as for example, water, or an organic fluid, including a liquefied normally vaporous or gaseous material, and can be solvents or nonsolvents for the active material. For example, the horticultural petroleum spray oils boiling in the range of from-about 275to about 575F., or boiling in the range of from about 575 to about 1,000F. and having an unsulfonatable residue of at least about 75 percent and preferably of at least about 90 percent, or mixtures of these two types of oils are particularly suitable liquid carriers.

The carrier can be mixed or formulated with the active material during its manufacture or at any stage subsequently. The carrier can be mixed or formulated with the active material in any proportion depending upon the nature of the carrier. One or more carriers, moreover, can be used in combination.

The compositions of this invention can be concentrated, suitable for storage and transport and contain,

10 are satisfactory, although lower and higher concentrations can be applied if necessary.

The compositions of this invention can also be formulated as dusts. These comprise an admixture of the active ingredient and a finely powdered solid carrier such as aforedescribed. The powdered carriers can be oil-treated to improve adhesion to the surface to which they are applied. These dusts can be concentrates, in which case a highly sorptive carrier is preferably used. These require dilution with the same or a different finely powdered carrier, which can be of lower sorptive capacity to a concentration suitable for application.

The compositions of this invention can also be formulated as wettable powders comprising a major proportion of the active ingredient mixed with a dispersant, i.e., a deflocculating or suspending agent, and, if desired, a finely divided solid carrier and/or a wetting agent. The active ingredient can te in particulate form or adsorbed on the carrier and preferably constitutes at least about 10 percent, more preferably at least about 35 percent by weight of the final pesticidal composition. The concentration of the dispersing agent should in general be between about 0.5 and about 5 percent by weight of the total composition, although larger or smaller amounts can be used if desired.

The dispersing agent used in the composition of this invention can be any substance having definite dispersant, i.e., deflocculating or suspending properties as distinct from wetting properties, although these substances can also possess wetting properties as well.

The dispersant or dispersing agent used can be protective colloids such as gelatin, glue, casein, gums, or a synthetic polymeric material such as polyvinyl alcohol and methyl cellulose, etc. Preferably, however, the

5 dispersants or dispersing agents used are sodium or calcium salts of high molecular weight sulfonic acids, as for example, the sodium or calcium salts of lignin derived from sulfite cellulose waste liquors. The calcium or sodium salts of condensed aryl sulfonic acids, for example, the products known as 37 Tamol 731, are also suitable.

The wetting agents used can be nonionic type surfactants, as for example, the condensation products of fatty acids containing at least 12, preferably 16 to 20, carbon atoms in the molecule, or abietic acid or napthenic acid obtained in the refining of petroleum oil fractions with alkylene oxides such as ethylene oxides or propylene oxides, or with both ethylene oxides or propylene oxides, as, for example, the condensation product of oleic acid and ethylene oxide containing about 6 to 15 ethylene oxide units in the molecule. Other nonionic wetting agents like polyalkylene oxide polymers, commercially known as Pluronics can be used. Partial esters of the above acids with polyhydric alcohols such as glycerol, polyglycerol, sorbitol, mannitol, etc, can also be used.

Suitable anionic wetting agents include the alkali metal salts. preferably sodium salts of sulfuric acid estcrs or sulfonic acids containing at least 10 carbon atoms in a molecule, for example, the sodium secondary alkyl sulfates, dialkyl sodium sulfosuccinates available under the registered trademark Teepol, sodium salts of sulfonated castor oil, sodium dodecyl benzene sulfonate, etc.

Granulated or pelleted compositions comprising a suitable carrier having the active ingredient incorporated therein are also included in this invention. These can be prepared by impregnating a granular carrier with a solution of an active ingredient or by granulating a mixture of a finely divided carrier and the active ingredient. The carrier used can contain a fertilizer or a fertilizer mixture, such as, for example, a super phosphate.

The compositions of this invention can also be formulated as solutions of the active ingredient in an organic solvent or mixture of solvents, such as, for example, alcohols; ketones, especially acetones; ethers; hydrocarbons; etc.

Where the toxicant itself is a liquid these materials can be sprayed upon crops without further dilution.

Petroleum hydrocarbon fractions used as solvents should preferably have a flash point about 73F., an example of this being a refined aromatic extract of kerosene. Auxiliary solvents such as alcohols, ketones, and polyalkylene glycol ethers and esters can be used in conjunction with these petroleum solvents.

Compositions of the present invention can also be formulated as emulsifiable concentrates which are concentrated solutions or dispersions of the active ingredient in an organic liquid, preferably a water-insoluble organic liquid containing an added emulsifying agent. These concentrates can also contain a proportion of water, for example, 50 percent by volume, based upon the total composition to facilitate the solution with water. Suitable organic liquids include, e.g., the above petroleum hydrocarbon fractions previously described.

The emulsifying agents can be of the type producing water-in-oil type emulsions which are suitable for application by low volume spraying, or an emulsifier of the type producing oil-in-water emulsions. Oil-in-water emulsions can be used, producing concentrates which can be diluted with relatively large volumes of water for application by high volume spraying or relatively small volumes of water for low volume spraying. In such emulsions, the active ingredient is preferably in a nonaqueous-phase.

The present invention is further illustrated in further detail by following examples, but it is to be understood that the present invention, in its broadest aspects, is not necessarily limited in terms of the reactants or specific temperatures, residence times, separation techniques, and other process conditions, etc.; or dosage levels, exposure times, test plants used, etc. by which the compounds and/or formulations described and claimed are preferred and/or used.

EXAMPLE 1 CH SH CH =CHCH NCO (major product) CH,-,SCH(CH;,)CH .NCO (minor product) Into a quartz pressure tube equipped with a magnetic stirrer and a Teflon screw valve, 49.8 grams (0.6 mole) of allyl isocyanate was placed. Then, 38.4 grams (0.8 mole) of methanethiol was condensed to it, using a dry ice bath. The tube containing the reaction mixture was placed into a water bath, thermostated at 15C., and mounted upon a magnetic stirrer drive. The stirred reaction mixture was then irradiated from a distance of 5 centimeters by a watt l-lanau ultraviolet immersion lamp having a high pressure mercury arc emitting a wide spectrum radiation.

The reaction mixture was sampled during the irradiation to determine the progress of the addition. Nuclear magnetic resonance spectroscopy (nmr) was found to be suitable, semiquantitative tool for the analysis of the samples. It showed that percent of the allyl isocyanate reacted in the first /-hour irradiation time. A total of 3 hours ultraviolet irradiation resluted in more than 95 percent conversion of the isocyanate. Nmr also showed that all the addition took place at the olefinic bond. It could also be determined by nmr that percent of the addition took place in an anti-Markovnikov manner to yield 3-methylthiopropyl isocyanate. About 10 percent of the adduct was of the opposite orientation, i.e., 2-methylthiopropyl isocyanate. The absence of ionic thiourethane adducts indicated that both adducts were formed by a selective, free radical mechanism.

Distillation of the reaction mixture in vacuo yielded 71.5 grams (91 percent) of the isomeric adduct mixtures as a clear, colorless, mobile liquid, boiling at 3335C. at 0.2 mm pressure. A fractional distillation resulted in an enrichment of the branched adduct isomer in the early fractions.

Elemental Analysis Calculated for C H NOS: C. 45.78; H, 6.91; S, 24.44; N, 10.67. Found: C, 45.52; H. 7.05; S, 24.38; N, 10.66.

EXAMPLE 2 Gamma lrradiation-lnitiated Addition of Methanethiol to Allyl Isothiocyanate CH SH CH CHCH NCS CH;,S(CH,) ,NCS (major product) CH SCH(CH;;)CH NCS (minor product) A mixture of 69.3 grams (0.7 mole) of distilled allyl isothiocyanate and 32.4 grams (0.675 mole) of methanethiol was reacted in a Pyrex pressure tube under the effect of gamma irradiation. The reaction was initiated from 10 cm distance with 4 Co plates emitting about 4,500 curies. Five hours irradiation resulted in about 40 percent conversion of the methanethiol to yield the allylic adducts. About 90 percent of the isomeric adducts was 3-methylthiopropyl isothiocyanate, while 10 percent was the branched Z-methylthiopropyl isothiocyanate.

The crude reaction product was distilled in vacuo to yield the isomeric mixture as a clear, light yellow liquid boiling at 7678C. at 0.6 mm pressure.

Elemental Analysis Calculated for the distillate, C H NS C, 40.78; H, 6.16; S, 43.55. Found: C, 40.38, H. 6.34; and S, 43.57.

A reaction of equimolar amounts of reactants under the above conditions resulted in 53 percent conversion in 16 hours. The isomeric; adduct mixture consisted of about 91 percent 3-methylthiopropyl isothiocyanate and 9 percent 'Lmethylthiopropyl isothiocyanate.

EXAMPLE 3 Ultraviolet Light-Initiated Addition of Methanethiol to Allyl losthiocyanate.

CH SH CH =3HCH NCS CH S (CH NCS (maj or product) CH SCH CH CH NCS (minor product) CH2=CHCH2NHSCH3 (minor product) A mixture of 69.3 grams (0.7 mole) of distilled allyl isothiocyanate and 33.6 grams (0.7 mole) of methanethiol was irradiated with two 75 watt Hanau immersion lamps for 127 hours at 16C., resulting in 90 percent reaction of the methanethiol. An nmr spectrum of the crude reaction mixture indicated that 80 percent of the adduct was 3-methylthiopropyl isothiocyanate. Eleven percent was the branched adduct, Z-methylthiopropyl isothiocyanate. About 9 percent of the adduct was N- allyl-S-methyldithiocarbamate, which resulted by the addition of the thiol to the isothiocyanate group.

Distillation of the crude reaction product in vacuo yielded a mixture of the 3- and 2-methylthiopropyl isothiocyanate as a liquid distillate identical with the product of the previous example.

EXAMPLE 4 Ultraviolet Light-Initiated Addition of 2-Propanethiol to Allyl isothiocyanate (CH CHSCH(CH;;)CH NCO (minor product) A mixture of 80.7 g (0.97 mole) of distilled allyl isocyanate and 73.9 g (0.97 mole) 2-propanethiol was irradiated with two Hanau lamps as described in the previous example. Nmr indicated that 5 hours of irradiation resulted in 79 percent, and 24 hours of total irradiation in 93 percent, reaction of the allyl isocyanate. After the removal of the unreacted volatile components of the mixture under 0.1 mm pressure, it could be estimated by nmr that the residue consisted of 95 percent 3-i-propylthiopropyl isocyanate and 5 percent Z-i-propylthiopropyl isocyanate.

Distillation of the crude residual product at 0.05 mm pressure yielded 140 g of the clear colorless liquid product boiling between 3436C. Based on the reacted amounts of starting materials, this amount corresponds to an isolated yield of 97 percent for the isomeric mixture of olefinic adducts.

Elemental Analysis Calculated for C H OSN: C,

52.80; H, 8.22; N, 8.79; S, 20.14. Found: C, 52.52; H, 8.28, N, 8.93; S, 19.81.

EXAMPLE 5 Ultraviolet Light-Initiated Addition of 2-Methyl-2-Propanethiol to Allyl lsocyanate A mixture of 84.2 g (1.01 mole) of distilled allyl isocyanate and 89.3 g (0.99 mole) of 2-methyl-2- propanethiol was irradiated as described in the previous example. Nmr spectroscopy of samples, taken at .periodic intervals from the reaction mixture, indicated allyl isocyanate conversions of 64 percent after 4 hours and of 93 percent after 64 hours irradiation. After the removal of the volatile reactants in vacuo, nmr analysis of the crude reaction product indicated that it was mostly 3-t-butylthiopropyl isocyanate.

Distillation of the crude product at 0.05 mm yielded 152 g of the clear, colorless liquid boiling between 3739C. This represents a 95 percent yield based on -the converted reactants. Nmr indicates a 95 percent minimum of the major isomeric adduct.

Elemental Analysis Calculated for C H OSN: C, 55.46; H, 8.72; N, 8.08; S, 18.5. Found: C, 55.31; H, 8.81; N, 8.08; S, 18.48.

EXAMPLE 6 Ultraviolet Light-initiated Addition of Benzenethiol to Allyl lsocyanate S(CH NC0 (major product) SCH(CH )CH NCO (minor product) A stirred mixture of 55 grams (0.5 mole) of benzenethiol and 43.6 grams (0.525 mole) of allyl isocyanate was irradiated in a quartz reaction vessel with a watt Hanau immersion lamp at 15C. Four hours irradiation resulted in about 50 percent conversion of the isocyanate as indicated by nmr. A total of 24 hours irradiation resulted in about 75 percent conversion to the two isomeric adducts resulting by addition to the olefinic bond. Nmr of the reaction mixture also indicated that the relative percentages of the adducts were 93 percent 3-phenylthiopropyl isocyanate and 7 percent 2-pheny1- thiopropyl isocyanate.

Fractional distillation of the mixture in vacuo yielded 55 grams (57.5 percent) of the isomeric adducts as a clear, colorless, mobile liquid boiling at 87-90C. at 0.1 mm. It was observed during distillation that the heating caused some reaction of the thiol with the isocyanate group.

Elemental Analysis: Calculated for C H ONS: C, 62.15; H, 5.73; N, 7.25; S, 16.59. Found: C, 62.28; H, 5.89; N, 7.19; and S, 16.74.

EXAMPLE 7 Gamma Irradiation-Initiated Addition of Benzenethiol to Allyl lsothiocyanate ation indicated the formation of 19 percent olefinic adduct. A total of 89 hours irradiation and 120 hours standing without irradiation resulted in the formation of byproducts, i.e. diadduct and cyanate adduct as indicated by nmr.

An attempted distillation of the reaction mixture at 0.1 mm pressure from a bath of 135C. resulted in the decomposition of the by-products according to the following reaction schemes:

CH2=CHCH2NHCS2 The volatile decomposition products were removed by distillation. Nmr indicated that the residual product (65 g) was mostly the olefinic adduct, i.e., 3-phenylthiopropyl isothiocyanate. Based on the amount of starting materials this corresponds to a yield of percent.

Elemental Analysis Calculated for C H S N: C, 57.38; H, 5.28; N, 6.69; S, 30.64. Found: C, 57.11; H, 5.46; N, 7.04; S, 30.45.

EXAMPLE 8 Ultraviolet Light-initiated Addition of Ethanedithiol to Allyl Isocyanate (major product) OC1 l(CH-,) S(CH SCH(CH )CH NCO (minor product) A stirred mixture of 94 grams 1.0 mole) of ethanedithiol at 182.6 grams (2.2 mole) of allyl isocyanate was irradiated in a quartz tube at 15C. by a watt Hanau ultraviolet immersion lamp. One hour irradiation resulted in the conversion of 55 percent of the isocyanate. A total of 5 hours irradiation converted about percent of the isocyanate. Removal of the excess allyl isocyanate by distillation gave a quantitative yield of a crude, residual product having an nmr spectrum corresponding to that of a mixture containing 92 percent of straight diadduct, ethylene bis-3-thiopropyl isocyanate, and 8 percent of the corresponding partially branched diadduct.

Distillation of the crude product in vacuo yielded 161.2 grams (62 percent) of the diadduct as a colorless, clear liquid, distilling at 147-1S0C. at 0.2 mm pressure. Nmr indicated that the rest of the product, which was a brown residue, also consisted mainly of the same diadduct.

Elemental Analysis Calculated for C H N O S C, 46.13; H, 6.19; N, 10.76; and S, 24.63. Found: C,

46.39; H, 6.32; N, 10.62; and S, 24.56.

EXAMPLE 9 Ultraviolet Light-Initiated Addition of Ethanedithiol to Allyl lsothiocyanate cyanate diadduct) A mixture of 29.7 grams (0.3 mole) of allyl isothiocyanate and 14.1 grams (0.15 mole) of ethanedithiol was irradiated in the manner described in the previous example. Nmr showed that hours irradiation resulted in the reaction of 45 percent of the allylic double bonds to form the corresponding allylic adducts. About 22 percent of the thiocyanate groups also reacted to form the cyanate adducts.

EXAMPLE 1O Gamma lrradiation-lnitiated Addition of Ethanedithiol to Allyl lsothiocyanate A mixture of 99 grams (1 mole) of allyl isothiocyanate and 47 grams (0.5 mole) of ethanedithiol was reacted with initiation from a gamma ray source as described in Example 2. Nmr indicated that 22 hours radiation resulted in 32 percent reaction of the allylic group. Subsequent irradiation for 70 hours plus 8 days standing resulted in a final reaction mixture, in which 57 percent of the allylic and 18 percent of the isocyanate double bonds were reacted.

3 ,8 84,9 1 17 1 8 CH =CHCH NHCS CH CH S CNHCH CH=CH2 A solution of 41.5 grams (0.5 mole) of allyl isocya- 2 CH =CH NCS HSCH- CH Sl-I The volatile decomnate and 72.25 grams (0.5 mole) of pposition products were removed by distillation. An nmr chlorobenzenethiol in 50 ml dimethyl sulfide was irraspectrum of the residual product 120 g) indicated that diated with an ultraviolet lamp in the manner described it was mostly the olefinic diadduct, i.e. 5 in Example 1. Nmr indicated that in 48 hours 32 per- 3-(ethylene)-bis-thiopropyl isothiocyanate. Based on cent of the allylic double bonds reacted with the thiol the amount of starting materials. the residual adduct to form the allylic monoadduct, i.e. 3-p-chlorophenylwas obtained in a yield of 82 percent. thiopropyl isocy'anate. No other products could be observed. EXAMPLE 1 l An attempt to fractionally distill the reaction mixture Ultraviolet Light-1nitiated Addition of Ethyl at 0.1 mm from a 160C. bath resulted in the formation Mercaptoacetate to Allyl lsocyanate of the diadduct as a residual product.

EXAMPLE l3 l5 Gamma Irradiation-Initiated Addition of Polythioether Dithiol to Allyl lsocyanate (allylic diadduct) A magnetically stirred mixture of grams (0.24 mole) of allyl isocyanate and l 10 grams (0.1 mole) of polythioether (PTE) dithiol of the above formula was irradiated with gamma rays for 16 hours in the manner described in Example 3. The crude reaction product was then heated at 130C. for 2 hours under 0.05 mm to remove the excess allyl isocyanate. A study of the nmr spectrum of the residual product indicated that a complete and selective addition of the PTE dithiol to form the allylic diadduct took place. A number average molecular weight determination of the product in ben- A mixture of 83 grams (1 mole) of allyl isocyanate and 120 grams (1 mole) of ethyl mcrcaptoacetate was irradiated by two ultraviolet lamps as described in Example l. Nmr analysis showed that most of the thio reacted in an hour. About 75 percent thiol addition occurred to the allylic double bond. To complete the reaction. the reaction mixture was irradiated for 14 more hours. The volatile components of the mixture were then removed at 0.05 mm. As a residual product, 190 grams (93 percent) of crude adduct was obtained. Nmr

indicated that it contained 80 percent of the major zene solution by a vapor pressure osmometer gave a product. i.e. 3-carboethoxymethylthiopropyl isocyavalue of 1,268. The calculated molecular weight of the nate and about 15 percent of the minor product, i.e. diadduct is 1,266. ethyl S-(N-allyl)-carbamoyl thiolacetate. Elemental Analysis Calculated for C H N O S An attempted distillation of the crude adduct yielded (diadduct of 1,168 molecular weight): C, 48.33; H, some 3-carboethoxymethylthiopropyl, isocyanate, as a 8.12; N, 2.39; S, 3843; Found: C, 48.13; H, 8.02; N, clear colorless liquid distilling at 97c. under 0.5 mm 2.40; S, 38.90. pressure with decomposition.

Elemental Analysis Calculated for C,,H,;,NO;,S: C, EXAMPLE 14 457,28; 6.44; N, -8 15.77- FOundI 5; H, Ultraviolet Light-Catalyzed Addition of Allyl 6 N, 6-75; 5515-63 lsocyanate to Polythioether Tetrathiol FHQSCHQCH2O-(CHQCHQSCHECI'IQSH) CH2=CHCH2NCO (Tetrathiol) EXAMPLE 12 Molecular Weight Calculated 795.5. Found 897 Ultraviolet Light-Initiated Addition of Number of Groups per Molecule Calculated pChlorobenzenethiol to Allyl lsocyanate Found (allylic lonoodduct) Q' SH diodduc t linked product is a very tough, hard polymer insoluble 35 ca cn scri cn s (on rico HQSCHQCHQ (Diadduct) Cli CI'i' SCIl- CI-I S CH 3llHC SCH CIT SCEI CHI CH CH SCH CH S I TH CH S CH CH S CH CH (Crosslinked Polythioether Thiourethane) A magnetically stirred mixture of 32.12 grams (0.39 EXAMPLE 16 mole) of allyl isocyanate and 80.7 grams (0.09 mole) 20 i of liquid polythioether (PTE) tetrathiol, derived from fglf zi Tholacetc Acld i g l zigs the addition of ethanedithiol to 1,2,4-trivinyl cyclohexc incn co 2 cociia ane, was irradiated with an ultraviolet lamp in the many adduct) ner described in Example 3. The progress of the allylic To 43.6 grams (0.525 mole) of stirred allyl isocyaaddition reaction was followed by nmr spectroscopy. In nate 38 grams mole) of thiolacetic acid Was added 28 hours, 69 percent of the allyl isocyanate reacted. A dropwise below 33C. in 15 minutes. An exothermic liquid product mixture consisting of a major amount of reaction started immediately with the addition of the triadduct and a minor amount of diadduct was formed. acid, which required icewater cooling during the addi- The unreacted allyl isocyanate was removed from this tion. The excess allyl isocyanate was subsequently remixture at 0.2 mm at room temperature. Subsequent moved at 0.25 mm overnight. The nmr spectrum of the heating of the liquid residual product at 135C. for 2 liquid, residual product showed that a quantitative hours resulted in crosslinking. This is due to a thermally yield of the ionic adduct derived byaddition to the isoinduced ionic reaction of the thiol groups with the isocyanate group was obtained.

cyanate groups to form thiourethane bonds. The cross EXAMPLE l7 Ultraviolet Light-Catalyzed Addition of in benzene.

EXAMPLE 15 n-Dodecanethiol to Allyl lsocyanate CH:!(CH2)HSH+ .1( Z)\I 2).1 Ultraviolet Light-Initiated Addltion of CH2=CHCH2NCO r dd ,B-Hydroxyethanethiol to Allyl Isocyanate 4O (O c mic i A mixture of 16.6 grams (0.2 mole) of allyl isocyaggggfi k fi 'g Sg nate and 40.4 grams (0.2 mole) of n-dodecanethiol is z 2 (allylic monoadduct) irradiated by an ultraviolet lamp in the manner described in Example 1 for 24 hours. An nmr spectrum HOCH CH S of the resulting reaction product shows that it is mostly (CH NHCO C1-1 CH S,,(CH NCO the straight chain olefinic adduct, i.e. 3-n-dodecy1 thio- (polythioether polyurethane polyadduct) propyl lsocyanate' A mixture of 91.3 grams (1.1 mole) of allyl isocya- EXAMPLE l8 nate and 78 grams (1 mole) of hydroxyethanethiol was Ultraviolet Light-Catalyzed Addition of Ethanethiol to irradiated with an ultraviolet lamp in the manner de- Allyl isocyanate scribed in Example 1 for 100 minutes. Nmr spectros- C2H5$H+CH2=CHCH2NCO C H5S(CHg)3NCO copy indicated that allylic monoaddition took place with a reactant conversion of 95 percent. The unre- A mixture of 16.6 grams (0.2 mole) of allyl isocyaacted volatile components of the mixture were renate and 12.4 grams (0.2 mole) of ethanethiol is irradimoved under diffusion pump vacuum at 1.5 X 10 ated at 30C. for 24 hours in the manner described in mm. The resulting residual product is 3-Bhydroxyethyl- Example 1 to yield the olefinic adduct, i.e. 3-ethy1thiothiopropyl isocyanate, a clear, colorless, mobile liquid. propyl isocyanate as the major product.

During 72 hours standing at room temperature, it was converted into a linear polythioether polythiourethane EXAMPLE 19 of 7589 number average molecular weight by self- Ultraviolet Light-Catalyzed Addition of Xylenethiol to Z-Methallyl lsocyanate polyaddition.

Elemental Analysis Calculated for C H NOS: C, A mixture of 27.6 grams (0.2 mole) of xylenethiol 9.63; H, 7.63; N. 9.64; S, 22.08. Found: C, 49.75; H,' and 16.6 grams (0.2 mole) of Z-methallyl isocyanate is 7.48; N, 8.78; 5. 21.68. irradiated as described in Examplc 1 for 24 hours. An

examination of the reaction mixture by nmr shows that the methallylic adduct, i.e. 3xylylthiopropyl isocyanate, is formed.

EXAMPLE 2O Azo-bis-lsobutyronitrile Catalyzed Addition of Methanethiol to Allyl lsothiocyanate A magnetically stirred mixture of 29.7 grams (0.3 mole) of allyl isothiocyanate, 15.4 grams (0.31 mole) of methanethiol and 3.3 grams (0.02 mole) of azo-bisisobutyronitrile was heated for 24 hours at 40C. A sub- POSTEMERGEMIE HERBICIDAL ACTIVITY CF ISOCYANATES AND ISUlHIOCYANATES Physiological Resgonae of Plants Injury to Crogw Injury to Weeds Overall lam Exam le Chl'miCBl Rate Sugar Soy Yellow yard Crab Buck- Morning Cro l-r d No. Structure L s./Acre Beets Corn Oats Clover Beans Cotton Mustard Foxtail Grass Grass wheat Glory Index lndt l H l CH CH NCS 10 8 C 6 C 3 C 10 C 9 C 10 C 9 C 10 C 10 C 10 C 3 C 10 C 7.6 8.6

2 CH SChCH CH hCO 10 5 c 3 c 3 c 9 c 9 c a c 7 c s c 5 c to c 6 c 5 c 6.1 6.5 s -s;a ca ca aco 1o 9 c 7 c 7 c 10 c 9 c 10 c 10 c 10 c 10 c 10 c 10 c 10 c 8.6 10.0 8 El l SCHCHCliNCO 1O 6C 70 6C 60 4C 9C 10C 3C 10C 10C 88 4.8 9.1

2 Z 2 2 Control CH =CHCH NCO 10 2 c 0 o a o 3 c 2 c 3 c 5 c 0 o 1.6 2.1 Control CH C0 2 n o o 10 n s 1) 9 c 10 c 0 o o 10 n 10 n 6.1 5.0

Cl (1|) 2: No visible effect. g: Slight injury; lant usually recovered with little or no reduction in top growth. 4-6: Moderate injury; planfs usually recovered but with reduced top growth. 7

lants killed. 2: Caustic. Q: Distorted.

sequent examination of the reaction mixture showed that a free radical addition to form 3-methylthiopropyl isocyanate occurred with percent conversion. In 96 houurs the conversion was 70 percent.

EXAMPLE 21 Thiol-Allylic lsocyanate and lsothiocyanate Adducts as Post-Emergence Herbicides A number of the adducts from those prepared in the previous examples were evaluated for post-emergence herbicidal activity in this example. The test procedure employed was as follows:

Appropriate crop plant and weed species were seeded by growth-time requirement schedules in individual disposable four-inch square containers, watered as required, and maintained under greenhouse conditions. When all crop plants and weeds had reached suitable growth development, generally first true leaf stage, plants and weeds appropriate to pertaining test requirements were selected for uniformity of growth and development. One four-inch container of each plant and weed, averaging six (Corn) to fifty (Crabgrass) or more plants or weeds per individual container, was then placed on carrying tray for treatment. Generally, six crop and six weed containers were used in each evaluation.

Candidate compoundsv were dissolved in acetone and, as appropriate, diluted in water containing wetting and emulsifying agents. Although isocyanates can react Severe injury; plants usually did not recover. 01 All EXAMPLE 22 Pesticidal Spectrum of 3-Methylthiopropyl isothiocyanate 3-Methylthiopropyl isothiocyanate, the product of Example 2, was examined in various standard pesticidal screening tests for its pesticidal activity.

. An aqueous emulsion containing 0.05 percent of the active chemical was found to kill, as a systemic poison, pea asphids.

When applied as an acetone solution at a rate of 100 lbs. active material per four-inch deep acre, the chemical completely controlled the root knot nematode on tomatoes.

When tested as a foliar fungicide on 6-8 inch high wheat plants, an acetone solution containing 0.5 percent of the chemical completely protected the plants against the cereal leaf rust, Puccinia recondita.

As a soil fungicide, the chemical was active against Rhizoctonia from cotton and Fusarium from tomato. For a positive effect, the compound was applied as an acetone solution at a rate of 36 lbs. per acre active material to the soil.

It should be understood from the foregoing that the above description is merely illustrative of the preferred embodiments and specific examples of the present invention and that in all of which embodiments and examples, variations, such as, e.g. those previously described, can be made by those skilled in the art without departing from the spirit and purview thereof, the in- .vention being defined by the following claims.

' What is claimed is:

1. Compounds of thegeneral formula with water the results were not significantly influenced wherein l is a positive integer of from 1 to 12. and n when, instead of the acetone solutions, aqueous emulsions were used for spraying the containers.

The application rate was ten pounds per acre and, as controls," allyl isocyanate and the sodium salt of 2,4- dichlorophenoxy acetic acid were used at the 10- and is a positive integer of from 1 to 100.

2. Compound of the formula [CH S CH CH CH N=C=O] 3. 3-,8-hydroxyethylthiopropyl isocyanate. 

1. COMPOUND OF THE GENERAL FORMULA
 2. COMPOUND OF THE FORMULA
 3. 3-B-HYDDROETHYLTHIOPROPYL ISOCYANATE. 